Abstract

Aquaponics is an important technique that entirely depends on fish feed, which is expensive and accounts for up to 60% of total variable costs. Black soldier fly larvae (BSFL) meal is one alternative to fishmeal in aquaponics systems. To promote the use of sustainable alternative aquaculture feed instead of fish meal, this study investigated the effect of replacing fish meal with BSFL meal on African catfish (Clarias gariepinus) performance (survival and growth) and water quality in aquaponics. The study employed the Randomized Complete Block Design (RCBD). A total of 135 catfish fingerlings were stocked in three replicates across nine 100-liter water barrels (filled with 60 L of water) and fed twice daily for 56 days. For acclimatization, fingerlings were fed commercial feed for two weeks. Water cycled through the hydroponic media grows bed using an automatic timer (15 min every hour, day and night). Fish meal was replaced with black soldier fly larvae meal at 0% (BSFL0), 30% (BSFL30), and 50% (BSFL50). One-Way Analysis of Variance (ANOVA) analyzed the data using JMP 16 software. Water parameter results showed no significant (p > 0.05) effect of black soldier fly larvae meal on pH, electrical conductivity, ammonium, nitrite, and nitrate. Diet types had no significant (p > 0.05) effect on survival, weight gain, specific growth rate, feed conversion ratio, feed intake, or length gain. This study implies that 30 and 50% of fishmeal can be successfully replaced with black soldier fly larvae meal in aquaponics without affecting water quality or catfish growth performance. Therefore, using black soldier fly larvae meal should be promoted to increase African catfish production in aquaponics.

Key words: Aquaponics, hydroponics, aquaculture, Hermetia illucens, Clarias gariepinus, fishmeal.